Resistance to acid attack of alkali-activated binders: Simple new techniques to measure susceptibility. (30th September 2017)

• Record Type: Journal Article
• Authors: Mellado, Ana; Pérez-Ramos, Martha Iris; Monzó, José; Borrachero, María Victoria; Payá, Jordi
• Is Part Of: Construction & building materials. Volume 150(2017)
• Page Start: 355
• Page End: 366
• Publication Date: 2017-09-30
• Subjects: Alkali-activated binder -- Durability -- Acid attack -- Acid neutralisation capacity -- Mass loss -- Consumed acid; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2017.05.224
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: Two new, simple methods for assessing resistance to acid attack have been proposed. Low calcium alkali-activated pastes showed the best resistance to acid attack. Acid neutralisation capacity (ANC) was measured for at pH 7, 4 and 2. The proposed ANC combined-pH assay is a good alternative for individual tests. Mass loss and acid consumption were proposed tests for studying monolithic samples. Abstract: Two rapid tests were developed to evaluate the resistance to acid attack by ordinary Portland cement (OPC) and alkali-activated pastes. Acid neutralisation capacity (ANC) at pH 7, 4 and 2 was monitored with powdered pastes. In parallel, a 'combined-pH assay' with a single sample was used to sequentially assess ANC at different pH values. A mass loss/consumed acid monitoring technique has been also developed in order to assess monolithic samples. The OPC paste showed the most degradation. Among the alkali-activated pastes, those with the lowest calcium content (fly ash and spent-FCC catalyst) had the best performance.